Search results
Results From The WOW.Com Content Network
wait normally returns the exit status of the last job which terminated. It may also return 127 in the event that n specifies a non-existent job or zero if there were no jobs to wait for. Because wait needs to be aware of the job table of the current shell execution environment, it is usually implemented as a shell builtin .
In Unix and other POSIX-compatible systems, the parent process can retrieve the exit status of a child process using the wait() family of system calls defined in wait.h. [10] Of these, the waitid() [ 11 ] call retrieves the full exit status, but the older wait() and waitpid() [ 12 ] calls retrieve only the least significant 8 bits of the exit ...
The jobs command will list the background jobs existing in the job table, along with their job number and job state (stopped or running). When a session ends when the user logs out (exits the shell, which terminates the session leader process), the shell process sends SIGHUP to all jobs, and waits for the process groups to end before ...
Remote command execution Version 7 AT&T UNIX val: SCCS Optional (XSI) Validate SCCS files System III vi: Text processing Optional (UP) Screen-oriented (visual) display editor 1BSD wait: Process management Mandatory Await process completion Version 4 AT&T UNIX wc: Text processing Mandatory Line, word and byte or character count Version 1 AT&T ...
In particular, the POSIX specification and the Linux man page signal (7) require that all system functions directly or indirectly called from a signal function are async-signal safe. [6] [7] The signal-safety(7) man page gives a list of such async-signal safe system functions (practically the system calls), otherwise it is an undefined behavior ...
If a process in the "running" state needs to wait for a resource (wait for user input or file to open, for example), it is assigned the "blocked" state. The process state is changed back to "waiting" when the process no longer needs to wait (in a blocked state). Once the process finishes execution, or is terminated by the operating system, it ...
The last string is the command that started the process. The state of a process can be changed using various commands. The fg command brings a process to the foreground, while bg sets a stopped process running in the background. bg and fg can take a job id as their first argument, to specify the process to act on.
Command-line completion generally only works in interactive mode. That is, it cannot be invoked to complete partially typed commands in scripts or batch files, even if the completion is unambiguous. The name tab completion comes from the fact that command-line completion is often invoked by pressing the tab key.